DOCSLIB.ORG

Research Memorandum

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Research Memorandum RM A50K07 NACA RESEARCH MEMORANDUM AERODYNAMIC STUDY OF A WING-FUSELAGE COMBINATION EMPLOYING A WING SWEPT BACK 63° - EFFECTIVENESS AT SUPERSONIC SPEEDS OF A 30-PERCENT CHORD, 50- PERCENT SEMISPAN ELEVON AS A LATERAL CONTROL DEVICE By Robert N. Olson and Merrill H. Mead Ames Aeronautical Laboratory Moffett Field, Calif. NATIONAL ADVISORY COMMITTEE FOR AERON AU TICS WASH INGTON January 18, 1951 Declassified April 8, 1957 1 NACA RM A50K07 NATIONAL ADVISORY COMMITTEE FOR AERONATITI CS RESEARCH MEMORANDUM AERODYNAMIC STUDY OF A WING-FUSELAGE COMBINATION EMPLOYING A WING 0 SWEP"r BACK 63 - EFFECTIVENESS AT SUPERSONIC SPEEDS OF A 30-PERCENT CHORD, 50-PERCENT SEMISPAN ElEVON AS A LATERAL CONTROL DEVICE By Robert N. Olson and Merrill H. Mead SUMMARY The effectiveness of a 5O-percent-semispan, constant-percent-chord elevon and of uppe~urface spoilers as lateral-control devices for a wing-fuselage combination employing a wing swept back 630 has been determined experimentally for the range of Mac.h numbers from 1.2 to 1.7 at a Reynolds number of 1.5 million. The results are compared with calculated values of the rolling-moment-effectiveness parameter CZ Q as obtained by the application of the linearized theory of supersonlc flow. For the elevon, results indicate that only about half of the rolling-moment effectiveness predicted by linear theory was realized. The variation of Mach number had little effect on the rolling-moment effectiveness of the elevon over the range investigated (Mach numbers of 1.2 to 1.7). Increasing angle of attack in the range of 00 to 100 had a moderate, adverse effect on the rolling-moment effectiveness of the elevon at a Mach number of 1.2; however, this effect diminished wi th increasing Mach number and became inappreciable in the range of 1.5 to 1.7 Mac.h number. The lateral-control characteristics of the elevon were little affected by variation of sideslip angle in the range from 50 to _5°. Elevon deflection produced small adverse yawing moments at positive angles of attack, w.hich were of suc.h small magnitude as to be of little concern. The upper-surface spOilers, having a maximum projection equal to the maximum wing-section thickness, were found to be inferior to the elevons for lateral control of this model because of a rapid loss in 0 effectiveness above an angle of attack of 4 • J 2 NACA RM A50K07 The present elevon was found to be more than adequate for rolling control of this wing-:fuselage combination if the wing were rigid; hovi­ ever, aeroelastic effects, computed from an approximate strip theory, were found to influence the rolling effectiveness of the elevon to the extent that structural considerations would be of prime importance in the final estimation of required elevon size. INTRODUCTION An investigation was made to determine means of attaining adequate lateral and longitudinal control for a wing-fuselage combination designed for efficient flight at supersonic speeds. This wing-fuselage combination, designed according to the theory advanced by J ones in ref­ erence 1, employed a wing of aspect ratio 3.5, taper ratio 0.25, and 630 sweepback of the leading edge. The results of wind-t unnel tests a t supersonic speeds to determine the effectiveness of a 3O-percent chord, 5O-percent-semispan elevon as a longitudinal control for this wing­ fuselage combination are presented (along with drag and hinge-moment data) in reference 2. The present report presents the results of a wind-tunnel investigation at supersonic speeds to determine the lateral­ control characteristics of this elevon. The lateral-control character­ istics of upper-surface, 5O-percent-semispan, outboard spoilers were also investigated. NOTATION All moment coefficients were referred to the stab ility axes wi th the origin located at the quarter-chord point of t he mean aerodynamic chord projected to the fuselage center line. rolling-moment coefficient (rolling moment) qSb damping-moment coefficient in roll; the rate of change of rolling­ moment coefficient C1 with wing-tip helix angle pb/2V, per radian C elevon rolling-moment-effectiveness parameter for constant angle of 1 o attack(dC 1 ) do a. Cn yawing-moment coefficient referred to quarter-chord point of mean aerodynamic chord (yaWing moment) qSb NACA RM A50K07 3 M Mach number (Via) R Reynolds number (pvc/~) S wing area~ square feet V airspeed, feet per second a speed of sound, feet per second b wing span~ feet b/2 (1 2 c dY), c wing mean aerodynamic chord 0 :feet b/2 f c dy o c local wing chord measured parallel to plane of symmetry, feet p angular velocity in roll, radians per second pb wing-tip helix angle, radians 2V q dynamic pressure (~V2), pounds per square :foot ~ angle of attack o:f :fuselage center line~ degrees ~ angle o:f sideslip, positive with right wing leading~ degrees 5 angle between wing chord and elevon chord, measured in a plane perpendicular to the elevon hinge line~ positive :for downward deflection with respect to the wing, degrees p mass density o:f air, slugs per cubic :foot ~ viscosity o:f air, slugs per foot-second Coefficients indicated with a prime (.) are uncorrected :for tunnel pressure gradient and flow inclination. APPARATUS AND TEST METHODS The investigation was conduct~d in the Ames 6- by 6-foot supersonic wind tunnel which is equipped with an asymmetric adjustable nozzle per­ mitting a variation in Mach number from 1.2 to 2.0 in the pressure range 4 NACA RM A50K07 of 2 to 20 pounds per s'luare inch absolute. However, due to certain vibration di:fficulties of the present model support system, the Mach number range is temporarily limited to a maximum of 1.7. The strain-gage balance and instrumentation are described in detail in reference 2. The model, pertinent dimensions of which are presented with a plan form sketch in figure 1, is shown mounted in the test section in the photograph of figure 2. The wing was untwisted, had 00 incidence, and was composed of NACA 0010 airfoil sections perpendicular to the leading edge. A ~ercent-chord elevon was mounted on the outboard 50 percent of the right wing panel. Spoilers, in heights up to the maximum wing­ section thickness, were constructed of aluminum alloy angles and were located successively at 40-, 50-, and 6o-percent-chord stations of the outboard half of the right wing panel. The wing and elevon were of solid-steel construction, while the fuselage was of hollo~teel con­ struction to permit the installation of the four-component strain-gage balance. A cutaway schematic drawing showing this installation is pre­ sented in reference 2. The fuselage was designed on the basis of mini­ mum wave drag for a given volume and length and had a fineness ratio of 12.5, including that portion of the body cut off to provide a method of attaching the model to the sting support. To shorte~ the testing time necessary for the lateral-control­ effectiveness investigation, the model was mounted in the test section with the plane of the wing placed vertically. With the model mounted in this manner, the present model support system permits continuous variation of the angle of sideslip during the test. Changing angle of attack, however, entailed changing the model support sting for each desired angle of attack. Side forces, rolling moments, and yawing moments were measured over a Mach number range from 1.2 to 1.7 at a Reynolds number of 1.5 million. The data were then transferred to stability axes and reduced to final coefficient form. Force measurements were made at nominal angles of sideslip of _50, -2.5°, 00 , 2.50 , and 50 for angles of attack of 00 , 0 0 5 1 and 10°. The elevon deflection was varied in 10 increments from 10° to -300 • The angle of sideslip of the model was determined optically by means of a cathetometer. The control-surface deflections, however, could not be determined during tests but were measured under stat ic conditions before each test and corrected for deflection under aero­ dynamic loading, using constants determined from static loading tests . The angle of attack was fixed for each test condition by us ing a sting bent to the desired angle. Since the angles of attack could not ------ ------------ NACA RM A50K07 5 be measured during the test, the angle of attack was measured initially under static conditions and corrected for deflection under aerodynamic load, using constants determined from static loading tests. REDUCTION OF DATA Since the force and moment strain gages were located inside the model, there were no direct foree tares due to aerodynamic forces on the sting. Effects of support interference, for the present investi­ gation, are confined to changes in base pressure and thus an effect on drag. (See reference 3.) Although the variations in stream curvature existing in the test section of the Ames 6- by 6-foot wind tunnel (discussed in reference 4) are such that lateral characteristics of a highly swept wing-body cam­ bination such as the present configuration, tested at Mach numbers other than 1.4, would be subject to some doubt, values of the incremental aerodynamic coefficients due to elevon deflection are reliable. Be cause of the axial variations in stream angle at Mach numbers above and below 1.4, however, it is difficult to determine the effective model angle of sideslip when testing with the plane of the wing vertical. Therefore, the angles of sideslip referred to in the report are nominal angles referenced to the borizontal plane and as such restrict the significance of the angle-of-sideslip eff ect s on the control-surface-effectiveness parameters to a qualitative indication as to t rends with Mach number.
Load more

Recommended publications
  • Actuator Saturation Analysis of a Fly-By-Wire Control System for a Delta-Canard Aircraft
    DEGREE PROJECT IN VEHICLE ENGINEERING, SECOND CYCLE, 30 CREDITS STOCKHOLM, SWEDEN 2020 Actuator Saturation Analysis of a Fly-By-Wire Control System for a Delta-Canard Aircraft ERIK LJUDÉN KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF ENGINEERING SCIENCES Author Erik Ljudén <[email protected]> School of Engineering Sciences KTH Royal Institute of Technology Place Linköping, Sweden Saab Examiner Ulf Ringertz Stockholm KTH Royal Institute of Technology Supervisor Peter Jason Linköping Saab Abstract Actuator saturation is a well studied subject regarding control theory. However, little research exist regarding aircraft behavior during actuator saturation. This paper aims to identify flight mechanical parameters that can be useful when analyzing actuator saturation. The studied aircraft is an unstable delta-canard aircraft. By varying the aircraft’s center-of- gravity and applying a square wave input in pitch, saturated actuators have been found and investigated closer using moment coefficients as well as other flight mechanical parameters. The studied flight mechanical parameters has proven to be highly relevant when analyzing actuator saturation, and a simple connection between saturated actuators and moment coefficients has been found. One can for example look for sudden changes in the moment coefficients during saturated actuators in order to find potentially dangerous flight cases. In addition, the studied parameters can be used for robustness analysis, but needs to be further investigated. Lastly, the studied pitch square wave input shows no risk of aircraft departure with saturated elevons during flight, provided non-saturated canards, and that the free-stream velocity is high enough to be flyable. i Sammanfattning Styrdonsmättning är ett välstuderat ämne inom kontrollteorin.
    [Show full text]
  • Stabilizer PLUS 7-Channel Receiver Essential Instructions
    Lemon RX Stabilizer PLUS Receiver – Essential Instructions v1.1 Lemon RX Stabilizer PLUS 7-Channel Receiver Essential Instructions Contents Introducing the Lemon StabPLUS ............................................................................................................ 2 Functions ........................................................................................................................................................ 2 Transmitter Requirements .............................................................................................................................. 2 Servos and Power Sources .............................................................................................................................. 3 Setting up the StabPLUS ......................................................................................................................... 4 Installation ...................................................................................................................................................... 4 Binding ............................................................................................................................................................ 5 Setting Failsafe ................................................................................................................................................ 5 Test Flying .............................................................................................................................................. 6 Preparing
    [Show full text]
  • 09 Stability and Control
    Aircraft Design Lecture 9: Stability and Control G. Dimitriadis Introduction to Aircraft Design Stability and Control H Aircraft stability deals with the ability to keep an aircraft in the air in the chosen flight attitude. H Aircraft control deals with the ability to change the flight direction and attitude of an aircraft. H Both these issues must be investigated during the preliminary design process. Introduction to Aircraft Design Design criteria? H Stability and control are not design criteria H In other words, civil aircraft are not designed specifically for stability and control H They are designed for performance. H Once a preliminary design that meets the performance criteria is created, then its stability is assessed and its control is designed. Introduction to Aircraft Design Flight Mechanics H Stability and control are collectively referred to as flight mechanics H The study of the mechanics and dynamics of flight is the means by which : – We can design an airplane to accomplish efficiently a specific task – We can make the task of the pilot easier by ensuring good handling qualities – We can avoid unwanted or unexpected phenomena that can be encountered in flight Introduction to Aircraft Design Aircraft description Flight Control Pilot System Airplane Response Task The pilot has direct control only of the Flight Control System. However, he can tailor his inputs to the FCS by observing the airplane’s response while always keeping an eye on the task at hand. Introduction to Aircraft Design Control Surfaces H Aircraft control
    [Show full text]
  • 10CAG/10CHG/10CG-2.4Ghz 10-CHANNEL RADIO CONTROL SYSTEM
    10CAG/10CHG/10CG-2.4GHz 10-CHANNEL RADIO CONTROL SYSTEM INSTRUCTION MANUAL Technical updates and additional programming examples available at: http://www.futaba-rc.com/faq Entire Contents ©Copyright 2009 1M23N21007 TABLE OF CONTENTS INTRODUCTION ........................................................... 3 Curve, Prog. mixes 5-8 ............................................. 71 Additional Technical Help, Support and Service ........ 3 GYA gyro mixing (GYRO SENSE) ............................... 73 $SSOLFDWLRQ([SRUWDQG0RGL¿FDWLRQ ........................ 4 Other Equipment ....................................................... 74 Meaning of Special Markings ..................................... 5 Safety Precautions (do not operate without reading) .. 5 Introduction to the 10CG ............................................ 7 GLIDER (GLID(1A+1F)(2A+1F)(2A+2F)) FUNCTIONS . 75 &RQWHQWVDQG7HFKQLFDO6SHFL¿FDWLRQV........................ 9 Table of contents........................................................ 75 Accessories ............................................................... 10 Getting Started with a Basic 4-CH Glider ................ 76 Transmitter Controls & GLIDER-SPECIFIC BASIC MENU FUNCTIONS ........ 78 6ZLWFK,GHQWL¿FDWLRQ$VVLJQPHQWV ............................. 11 Model type (PARAMETER submenu) ........................... 78 Charging the Ni-Cd Batteries ................................... 15 MOTOR CUT ................................................................ 79 Stick Adjustments ....................................................
    [Show full text]
  • Bob Loschke and Ken Dyson Interview by Peter Westwick
    Ken Dyson and Robert Loschke interview by Peter Westwick, 9 January 2012. WESTWICK: I'm sitting here with Ken Dyson and Bob Loschke on January 9th, 2012. Instead of the usual approach of going back and doing extended career oral histories, we're going to do a more focused one capitalizing on these two gentlemen's shared experiences, especially on Have Blue and the F-117A and Stealth. Maybe by way of getting into the conversation, if you could each just share how you made your way into the Have Blue and Stealth program. Ken, maybe start with you. Around 1976 you started working on classified programs. You're up at Edwards doing F-15 test piloting, still in the U.S. Air Force. And as a U.S. Air Force test pilot is when you got involved with the program? DYSON: That's right. I don't know if you want to start with me. Bob was aboard it before I was. But you can go ahead and lead with me if you want. WESTWICK: So let's start with Bob then. This is Bob's voice. LOSCHKE: I first started in what became the Have Blue program in about 1974. The S-3A program had just been winding down. I'd been involved in the control system on that airplane. It was a carrier-based ASW aircraft. I had had some previous contact with Ben Rich on some other work, and he recalled that I had done control system things, so he requested that I come over to the Skunk Works at that point and help them make a proposal.
    [Show full text]
  • Four Servo Elevon Mixing with Y-Cable
    Four Servo Elevon Mixing with Y-Cable On the Hercules, we have split the elevons in half, making four small elevons for the following reasons: 1. We want the aileron or roll movement only on the wingtips where it is the most effective and doesn’t destabilize the wing and cause increased drag. 2. We want elevator movement across the entire wing so that the wing does not have any “dead areas” without reflex on the elevons. If you have a different radio than the DX6i, you may have a different programming sequence, but this will hopefully give you the concepts you need. The goal is for all of the surfaces move up and down together for elevator, while only the tips will move for ailerons. Below the instructions are a couple commonly asked questions about the Hercules and the four-servo setup. Install the four elevon servos in the wing 1. Install each servo close to the center of each of the elevon they will control. 2. Make sure they are close enough that the push rods will reach the servo horn on the flap. 3. Do not mount servos directly behind the motor where split rudders may be installed. 4. Servo arms should point sideways, towards the wingtips, except for the R center elevator. 5. Connect the 2 inside servos with a “Y” connector. 6. Add servo extension wires as needed so the outside servos can reach the receiver. Plug the servos into the receiver in the following order. 1. R tip elevon is plugged into the receiver’s #6 slot that may be called Aux #1 or Flap 2.
    [Show full text]
  • Flight Test Results of the F-8 Digital Fly-By-Wire (DFBW) Control System
    FLIGHT TEST EXPERIENCE WITH THE F-8 DIGITAL FLY-BY-WIRE SYSTEM Kenneth J. Szalai NASA Flight Research Center SUMMARY Flight test results of the F-8 digital fly-by-wire (DFBW) control system are presented and the implications for application to active control technolo& (ACT) are discussed. The F-8 DFBW system has several of the attributes of proposed ACT systems, so the flight test experience is helpful in assessing the capabiliyies of those systems. Topics of discussion include the predicted and actual flight performance of the control system, assessments of aircraft flying qualities and other piloting factors, software management and control, and operational experience. I INTRODUCTION i In May 1972 the flight testing of the F-8 DFBW aircraft began. This aircraft, which used Apollo guidance and navigation system hardware, was the first to rely on a DFBW system for primary flight control. The design and development of the F-8 DFBW control system are described in references 1 to 3. This paper presents the major flight test results for the control system. A detailed description of the system's software development and verification is given in reference 4, and the backup control actuation systems are described in reference 5. The primary objectives of the flight tests were to evaluate the performance of the digital flight control system and to acquire operating experience with it. The program also served to determine whether the long-advertised advantages and capabilities of DFBW control systems could be realized. Many of these advantages, such as software flexibility, system reliability, and computational ability, make a DFBW system a logical candidate for active control technology applications.
    [Show full text]
  • Flight Control System Design for a High Altitude, Long Endurance Airplane: Sensor Distribution and Flexible Modes Control
    Flight Control System Design for a High Altitude, Long Endurance Airplane: Sensor Distribution and Flexible Modes Control Hamidreza Bolandhemmat* Abstract— This manuscript outlines the control system design Figure 1: The undefomed Aquila airplane shape (gray) is compared to the process for a solar-powered unmanned high-altitude long deformed shape under the first symmteric bending and torsion elastic modes endurance flying wing aircraft, called Aquila, which was (coloured as function of the deformation magnitude); Left picture portrayes the front view while the right shows the side view. developed by the Facebook Connectivity Lab to serve as communication backhaul for remote and rural connectivity. With 400kg mass and 42m wing-span, it was designed to autonomously fly at stratospheric altitudes of the atmosphere between 18 and 26km for months at a time. I. INTRODUCTION Performance of the solar-powered High-Altitude Long Endurance (HALE) aircrafts in closing the energy cycle on winter solstice days could be notably enhanced by increasing the aspect-ratio1 (L/D>35) and decreasing the weight. Both, however, contribute to higher structural flexibility and thereby existence of lightly damped “coupled” rigid body and elastic This article aims at demonstrating such a methodology in modes which could result in adverse Aeroservoelastic (ASE) the design of flight control and active flutter suppression phenomena such as Limit Cycle Oscillations (LCO), and systems for the Aquila aircraft. Challenges in specifying (body-freedom) flutter. LCO is used to describe sustained, effective sensor and servo placements on the aircraft to provide periodic, but not catastrophically divergent aeroelastic sufficient observability and controllability of the prevalent motions.
    [Show full text]
  • Civil Air Patrol's ACE Program
    Civil Air Patrol’s ACE Program FPG-9 Glider Grade 5 Academic Lesson #4 Topics: flight, cause and effect, observation (science) Lesson Reference: Jack Reynolds Courtesy of the Academy of Model Aeronautics (AMA) at http://www.modelaircraft.org/education/fpg-9.aspx (It includes a video on building and flying the FPG-9.) The video explanation, may also be found at https://www.youtube.com/watch?v=pNtew_VzzWg. Length of Lesson: 40-50 minutes Objectives: • Students will build a glider. • Students will experiment with “launch” technique, elevons, and rudders to determine how to best fly the glider. National Science Standards: • Content Standard A: Science as Inquiry • Content Standard B: Physical Science - Position and motion of objects • Content Standard E: Science and Technology - Abilities of technological design • Unifying Concepts and Processes - Form and function Background Information: (by Jack Reynolds, AMA Volunteer) Play has been defined as the work of children and, as such, toys are the tools of their work. If play is the work of children, the “art of fine play,” (fun with a purpose) is the work of teachers. Orville and Wilbur Wright first learned about flight when their father brought home a toy helicopter for their amusement Orville recalled that they played with it for hours, eventually designing and modifying the original many times. The FPG-9 derives its name from its origins, the venerable and ubiquitous foam picnic plate. The Foam Plate Glider is created from a 9-inch diameter plate, available in most grocery and convenience stores. It can be used for an engaging and safe exploratory activity to excite students and deepen their understanding about science and the physics of flight.
    [Show full text]
  • What's New In
    Design • Analysis • Research What’s New in AAA? Version 3.5.1 and Version 3.5 September 2013 AAA 3.5.1 contains various enhancements and revisions to version 3.5 and 3.4 as well as bug fixes. Section 1 shows the enhancements and modifications made to AAA. Major enhancements include new modules and calculations. The second section contains bug fixes. The AAA Manual describes the installation procedure and all modules. The manual is available in pdf format on the installation CD. What’s New in AAA 3.5.1? 1 1. Enhancements and Modifications – AAA 3.5.1 Differences between AAA 3.5.1 and AAA 3.5 are: 1. Cl and Cn have similar input/output parameters as Cl and Cn δrv δrv δr δr 2. The limits on material weight factors have been removed in Class II Weight. 3. The pylon root sweep angle can be defined. 4. Thrust from Drag in the Propulsion module is added to the Recalculate All module. 5. Cost Escalation Factor is updated through August 2013 6. The total wetted areas for nacelles, pylons, tailbooms, stores and floats are now calculated. 7. The airplane equivalent skin friction coefficient is now calculated based on airplane wetted area, C and wing planform area. Do 2. Enhancements and Modifications – AAA 3.5 Differences between AAA 3.5 and AAA 3.4 are: 1. Multiple segmented high lift devices can now be entered. 2. There is new option for Flap or Slat definition in the configuration dialog window 3. There is an additional Payload Reload mission segment option in weight sizing.
    [Show full text]
  • Radiolink At9s (Dsss&Fhss)
    RADIOLINK AT9S (DSSS&FHSS) INSTRUCTION MANUAL RADIOLINK ELETRONIC LIMITED Technical updates and additional programming examples available at: http://www. radiolink.com.cn INTRODUCTION Thank you for purchasing Radiolink 2.4 GHz 10CH remote control system -- AT9S. This system is extremely versatile, it is the most complete remote control device as so far in our product series, it can operate helicopter, fixed-wing, glider, aircraft, cars and boats. AT9S is the first transmitter with DSSS and FHSS hybrid dual spread spectrum, 16 channels pseudo random frequency hopping. QPSK modulation ensure excellent anti-interference performance, even can controlled normally in city center. The control distance is about 900 meters ground and 3400 meters air. Despite the powerful function, humanized menu is designed applicable to both beginners and skilled person. In order to better use remote control equipment and ensure flight safety, please read the instructions carefully, when we write the instruction to use the familiar and simple words to make it easy for beginners to understand the name and formulation. Suggestion: In order to fully enjoy the benefits of this remote control equipment and ensure flight safety, please read the instructions carefully and set up the device as described below, when we write the instruction to use the familiar and simple words to make it easy for beginners to understand the name and formulation. Please refer to the manual or call our after-sales (+86-0755-88361717) or log in BBS (such as www.rcgroups.com, https://www.facebook.com/Radiolink-1455452961436694/) to check the issues related answer to questions if you have any questions.
    [Show full text]
  • Design and Development of Flight Control Laws for Lca
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by National Aerospace Laboratories Institutional Repository DESIGN AND DEVELOPMENT OF FLIGHT CONTROL LAWS FOR LCA Shyam Chetty* and Girish Deodhare* The design and development of the flight control laws control law. The aircraft is made to roll about the velocity for LCA was started in early 1993 with the formation of vector in response to a roll stick input, to suppress the the National Control Law Team consisting of engineers kinematic coupling between a and the sideslip angle t V and scientists drawn from five national aeronautical re- especially at high a. In addition, the (3 build-up durin search and development institutions. The control laws g i nitiation of turns is minimised. The control law ensures a being developed by this team are independently verified roll rate demand from the roll stick and a (3 demand from and validated by an IVand V team and the design process, specifications, data and results are also audited by special- the rudder pedals. As the r3 build-up is minimised by the ists from British Aerospace UK. control law, the pilot need not operate the rudder pedals during turns. Due to inertial coupling between the pitch I The Light Combat Aircraft is a single engine, tail-less and the roll/yaw axes, the roll rate and sideslip demands delta wing aircraft which is designed to he aerodynami- are reduced during pitching manoeuvres. This is achieved i cally unstable in the longitudinal axis. In order to stabilise n the control law through interconnects from the pitch axis to the roll and yaw axes.
    [Show full text]